Moseley, 1875b emend. Brinkmann, 1917a
Body usually broad and flattened anteriorly, posterior end often distinctly narrowed and in some genera ending in broad caudal fin; dorsal blood vessel ends blindly in rhynchocoel a short distance behind the brain; mouth and proboscis pore separate; intestinal diverticula usually with ventral branch; myofibrillae present in lateral nerves; spermaries in two groups behind, alongside or in front of brain.
Genus Pelagonemertes
Genus Probalaenanemertes